The most famous political advertisement in American history aired only one time on television, but it's been viewed and referenced countless times, because it signaled such a radical shift in how candidates pitch themselves to the public [source: Geer]. Known simply as the "daisy ad," the minute-long slot was created by the advertising firm Doyle, Dane and Bernback on behalf of President Lyndon Johnson, who was seeking re-election against Republican Arizona Senator Barry Goldwater in 1964. It begins with a little girl counting petals on a daisy, and the camera gradually zooms in toward her pupil, which reflects a mushroom-cloud explosion. Then briefly, an ominous message flashes on the screen urging viewers to vote for Johnson because "the stakes are too high for you to stay home," the advertisement's undertones implying that siding with Goldwater -- or allowing him to win by not voting at all -- would mean siding with nuclear war.

The daisy ad was so effective at jabbing Goldwater with indirect, yet threatening, rhetoric, that it has been cited as the first attack ad in U.S. politics [source: Cone]. Prior to that seminal production, political advertisements typically functioned as truncated stump speeches rather than creative, evocative ventures [source: Dwyer]. Not surprisingly, Goldwater responded with outrage, accusing the Johnson campaign of harping on people's fears of nuclear warfare, but it was too late. The age of the attack ad had come to stay.

When the daisy ad beamed out to an estimated 50 million viewers, television commercials for political candidates hadn't been around all that long. The first aired in 1950 on behalf of Connecticut Senator and former advertising executive William Benton, who broadcast his commercial on screens set up in public areas like shopping centers and street corners, since few Americans at the time had televisions at home [source: PBS]. The novel trick worked, and Benton narrowly won re-election. Two years later, the 1952 presidential race cemented political commercials as a cornerstone feature of election campaigns. A televised Dwight Eisenhower chatted with viewers during "Eisenhower Answers America" segments, and his vice presidential running mate Richard Nixon quelled allegations that he had accepted illegal corporate funds with his "Checkers" speech, in which he cleverly admitted that his camera-friendly dog Checkers was, indeed, a gift from one of his supporters [source: PBS].

Since the daisy ad days, political advertising has become more pervasive, as well as increasingly negative with every election cycle, it seems. Although the Internet and blogosphere have raised the stakes for credibility in political attack ads, since they now can be quickly fact-checked and debunked, it's nevertheless those below-the-belt ads that have turned voter tides. For instance, the 1988 presidential showdown between then-Vice President George H.W. Bush and Massachusetts Governor Michael Dukakis produced two notable attack ads that helped push Bush into the Oval Office. In one, the Bush campaign aired footage of an uncomfortable-looking Dukakis awkwardly sporting combat gear and driving a tank as an ironic backdrop to highlight his alleged ineptitude on national defense. The other, paid for by a pro-Bush interest group, stoked racist anxieties and portrayed Dukakis as soft on crime by flashing a mug shot of convicted Massachusetts felon Willie Horton who raped a woman while released from prison on furlough, which Dukakis had instituted during his tenure [source: PBS].

More recently, in the 2004 presidential race, an interest group representing Vietnam veterans broadcast attack ads claiming that Democratic candidate John Kerry had lied to obtain some of his medals while serving in the navy during the Vietnam War. Although the allegations were later proven false, the commercials nevertheless dented Kerry's reputation and electability [source: PBS Newshour].

For an idea of just how big of a business political advertising has become, in 2012, campaigns around the United States for president, governor and Congress are expected to spend a staggering $3 billion on television advertising alone [source: Dingfelder]. But those dollars don't just go to the moving pictures on screen. These specialized commercials spring from a sophisticated industry that targets messaging toward its audience with the precision of experienced hunters lining up prey in their crosshairs.